Thermoplastic polymer yarns and films including dry lubricants and industrial textiles made therefrom

ABSTRACT

An extruded oriented thermo-plastic polymeric element for industrial textiles, and textiles comprising polymeric elements. The polymeric elements are constructed of a material selected from yarn material, fiber material and film, and comprise a thermoplastic polymer, and at least one dry lubricant, selected from molybdenum disulphide, tungsten disulphide, boron nitride, and a soft metal, the dry lubricant comprising particulate matter having an average particle size between about 0.05μ and about 100μ, and present in the polymeric element in an amount from between about 0.1% and about 10% parts by weight, based on a total weight of the polymeric element. The polymeric elements can be used as yarns in woven and non woven textiles, and as seaming elements. The polymeric elements provide increased abrasion resistance in industrial textiles, and reduced co-efficient of friction.

FIELD OF THE INVENTION

The present invention concerns oriented, thermoplastic polymer elements,including yarns, fibers and films which offer increased resistance toabrasion and provide a reduction in the frictional characteristics inindustrial textiles into which they are incorporated. Specifically theinvention concerns oriented thermoplastic polymer elements into whichdry lubricants such as particles of molybdenum disulphide, boron nitrideor tungsten disulphide have been incorporated in amounts of from about0.1% to about 10% by weight based on the total weight of the elements,and woven or nonwoven fabrics made from or incorporating the elements.

BACKGROUND OF THE INVENTION

Industrial textiles (also referred to as technical textiles) are used inmany consumer and industrial applications, either as a component of theend product, or in the manufacture of one or more components. Thesetextiles are typically woven structures made from polymeric yarnscomprising a polyester, polypropylene, polyamide, polyethylene, glassfibers or other similar materials; they may also be nonwoven structuresassembled from films, staple fibers, encapsulated yarn arrays andsimilar components such as are known in the art. It is also known toassemble industrial textiles from a plurality of helical coils, whichare intermeshed and interconnected in a hinged arrangement, by hinge orpintle yarns. The component yarns, fibers or films from which thetextile is assembled may be monofilaments, multifilaments, spun yarns,cabled yarns, homolayer or multilayer films and the like. One generalclass of industrial textiles to which the present invention isparticularly relevant is filtration and conveying fabrics and, inparticular, papermaking fabrics.

However, although the present invention is discussed below withparticular reference to papermaking fabrics, it is applicable to anytype of industrial textile intended for conveying or filtration andwhich can be constructed from polymeric elements, including, but notlimited to, textiles constructed by weaving, helical or spiral coilassembly, pre-crimped yarn assembly, and selectively slit and embossedfilm, in each case to provide a single layer textile, or one or moreouter layers in a multi-layer construction. In addition, as discussedfurther below, the present invention is applicable to seaming elementsfor industrial textiles, including such elements formed from films, oras spiral seaming coils, or as seaming lumens.

In modern high speed papermaking processes, a highly aqueous stockconsisting of about 99% water and 1% papermaking solids is ejected athigh speed and precision onto an endless moving forming fabric. Anascent web, which will be self coherent and consist of about 25%papermaking solids by the end of the forming section, is formed as thestock is drained through the fabric as it passes over various dewateringelements and drainage boxes. This web is then transferred from theforming fabric into the press section of the papermaking machine where,together with at least one press felt, it passes through one or morenips where additional fluid is removed by mechanical means. The web isthen transferred into the dryer section of the papermaking machine whereit is supported on one or more dryer fabrics as it passes in serpentinefashion over a series of heated rotating drums where much of theremaining moisture is removed by evaporative means. The finished sheetis then reeled into large rolls at the end of the papermaking machine,and further finishing processes may be applied. Tissue and towel formingprocesses are similar but employ a so-called through-air dryer (TAD)fabric to convey the sheet through an air drying section of thetissue-making machine where it is dried and various physical propertiesare created in the final product.

Forming fabrics, press felts, dryer and TAD fabrics are critical to thequality of the paper product that is ultimately produced on thepapermaking machine. In simplest terms, these fabrics are designed toallow fluid from the stock to pass through the fabric in a controlledmanner, while providing uniform support to the papermaking solids. Theyare also intended to provide consistent support for the paper web formedand conveyed by them. Each of these fabrics is uniquely designed foroptimal performance in the environment for which it is intended. Formingfabrics should be as thin as is possible, so as to minimize internalvoid volume and water carrying capacity, while max support for thepapermaking fibers and other solids they convey. Press felts provide avoid volume into which water that is expressed from the web in a pressnip may be carried away so as to dry the sheet. Dryer fabrics areengineered to carry and support the wet web while the remaining water isevaporated from the sheet. Considerable efforts have been made byvarious manufacturers of papermaking fabrics to provide textiles thatare thin yet sufficiently robust and dimensionally stable so as tosurvive the environmental forces to which they are exposed. Thesefabrics are routinely exposed to high temperatures and humidity, as wellas abrasive wear from their continuous sliding contact with the variousstationary components over which they travel at speeds in excess of1,000 meters per minute.

Industrial filtration and conveying fabrics, both woven and nonwoven,are employed in various applications, including but not limited towastewater treatment, water supply, food processing, pharmaceuticalprocessing, chemical processing, and pigment and coating processes. Likepapermaking fabrics, these more generic industrial textiles aretypically made from thermoplastic polymer yarns or films whoseproperties are selected and engineered in accordance with end userequirements.

In an effort to increase the performance characteristics of thesetextiles, a wide variety of yarn and film materials have been employedin their manufacture, including natural fibers, metals and, morerecently, yarns and films formed from thermoplastic polymers. Thepredominant polymers in use today in the manufacture of papermaking andindustrial filtration fabrics include polyesters, in particularpolyethylene terephthalate (PET), polybutylene terephthalate (PBT),polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN) and1,4 cyclohexanedimethanol-terephthalate-co-isophthalate (PCTA), as wellas their various known blends and copolymers, and nylons, such aspolyamide-6 and polyamide-6/12, and various blends and formulationsthereof. Other non-limiting examples of thermoplastic polymers known andused for such applications include blends of polyester and polyurethane(Monalloy®), polyether ether ketone (PEEK), and polyphenylene sulphide(PPS); others are known and used.

Papermaking fabrics, in particular forming and dryer fabrics, arecommonly woven using a thermoplastic polyester monofilament warpmaterial which is usually located in the machine direction (MD) of thefinal fabric, and either polyester or polyamide monofilaments as theweft material which are arranged in the cross-machine direction (CD), onthe machine side (MS) of the fabric where the majority of abrasive forceis applied transversely to the longitudinal dimension of themonofilament. The preferred polyester for these applications is PET;however, it is known to use PBT, PTT, PCTA and PEN, as well ascopolymers and blends containing PET and other polyesters. Polyamidesare generally preferred for use as at least a portion of the weftmaterial in forming fabrics due to their ability to resist abrasive wearin comparison to polyesters. However, it is well known that the physicalproperties of polyamides, in particular their hydrophilic nature andcrimp behaviour during fabric processing, introduce difficulties in bothmanufacturing (in particular the weaving, heatsetting and seamingprocesses) and the end application, where curl may occur in the outeredges of the forming fabric. These difficulties occur due to thediffering mechanical and thermal properties of polyamides as compared topolyesters. It is also known that polyamides are generally less inertthan polyesters in acidic environments and will deteriorate morequickly.

Polyester, in particular PET, is a stable polymer that moves throughfabric manufacturing processes from weaving to heatsetting and seamingwith relative ease due to its stable nature. End users of the wovenproduct seldom have difficulties with fabrics made from this material assuch fabrics tend to run without significant performance issues (e.g.skewing, creasing, etc) and can loop through both the paper formingstage and return/cleaning stages without notable difficulties. However,on more demanding applications in the papermaking machine, where thefabrics are exposed to higher than usual abrasive conditions, polyestermonofilaments can wear quickly when exposed to high vacuum levels asthey pass over multiple dewatering units. Previous attempts to improvethe MS wear resistance of these fabrics have focused on adding orsubstituting monofilaments comprised of other polymers that offeredbetter abrasion resistance. Such efforts are described, for example, byBhatt et al. in U.S. Pat. No. 5,169,711 and U.S. Pat. No. 5,502,120,both of which disclose blends of polyester and thermoplasticpolyurethanes for improved abrasion resistance over pure polyesters.Other similar efforts are known. A known advantage of the polymer blendmaterials described by Bhatt et al. in U.S. Pat. No. 5,169,711 and U.S.Pat. No. 5,502,120, in comparison to polyamides, is their crimpbehaviour during weaving and heatsetting, as well as their provenability to resist abrasive wear. These polyester/polyurethane blendstend to act more like polyester, which results in improved fabricprocessing.

At the seaming areas of industrial textiles, to minimize discontinuitybetween those areas and the adjacent textile body, various seamingelements are known and used which are constructed of polymers eitheridentical to, or closely compatible with, polymers from which thetextile body is constructed. Such seaming elements include, for example,spiral seaming coils, and various constructions designed to engage therespective textile edges and be connected together.

DISCUSSION OF PRIOR ART

Molybdenum disulphide has been utilized for many years as an additive topolyamides so as to improve the abrasion resistance and lower theoverall coefficient of friction of the polyamide material and therebyincrease the wear life of components made from this polymer. Such use ofmolybdenum disulphide as a component material for the manufacture ofpolyamide monofilament is known. For example, U.S. Pat. No. 4,370,375(Bond) discloses polyamide monofilaments containing molybdenumdisulphide and lithium bromide for use as transverse strands of wovenforming fabrics.

GB 2,315,499 (Draper) discloses microencapsulated photochromic dyesincorporated into the polymer matrix of 10-20 denier staple fibers usedin a press felt batt. Either the textile yarns or a textile coating maycontain the photochromic material. Draper discloses that other additivesincluding molybdenum disulphide may be incorporated into the dye microcapsules to enhance textile properties, e.g. to increase lubricity.

WO 00/55402 (Hinterkeuser) discloses a polyamide based monofilamentfiber that allegedly offers improved abrasion resistance properties incomparison to pure polyamide by incorporation into the polyamide of aneffective amount of molybdenum sulphide in a manner similar to thatdisclosed by U.S. Pat. No. 4,370,375 (Bond).

U.S. Pat. No. 5,585,430 (Patel et al.) discloses a pintle wire formed byextrusion from e.g. nylon (polyamide 6, 6/6, 6/10, 6/12), polyesters orcopolyesters, PEEK, PPS, and no more than 3 wt % of a schistoselubricant such as graphite, molybdenum sulphide, clays or a silicate.The schistose material allegedly eases insertion of the pintle wire intopress and dryer fabrics because of reduced drag or friction, and reduceswear between the pintle and seaming loops.

US 2009/0209695 (Yu et al.) discloses a thermoplastic compositioncomprising a mixture of from 10 to 98 pbw of a polycarbonate polymer,from 2 to 90 pbw of a polyester polymer, and from 0 to 5 pbw of apolylactic acid polymer. It is stated in the disclosure (see pg. 7,para. 41) that one or more fillers can be added to the composition,including molybdenum sulphide.

It is also known from U.S. Pat. No. 6,949,289 (Lawton et al.) to usemolybdenum disulphide as a coating; and known from US 2006/0110597(Koralek) and U.S. Pat. No. 4,719,066 (Wells et al.), to add molybdenumto polyesters and polyamides.

There is a well known need in the manufacture of industrial textiles,particularly those intended for use in papermaking processes, forpolymer elements, including yarns, fibers and films, which offerimprovements in wear resistance over polyester, while simultaneouslyreducing the frictional characteristic of these textiles in comparisonto similar fabrics formed from prior art materials, and which arefurther free of the attendant processing difficulties associated withpolyamides. The present invention seeks to provide such polymericelements, and textiles formed therefrom.

It has now been found that it is possible to provide significantimprovements by both increasing the abrasion resistance and reducing thefrictional characteristics of industrial textiles, by providing extrudedand oriented thermoplastic polymer elements for a wide range of end useapplications, such polymeric elements being provided in suitable forms,including as yarns, fibers or films, and containing an appropriateamount of at least one dry lubricant selected from a group of suitabledry lubricants.

SUMMARY OF THE INVENTION

In the following discussion, the term “yarn” refers to a continuousstrand. Yarns can include monofilaments formed from orientedthermoplastic polymers as noted above, and which may or may not have asheath-core construction, and can also include polymeric multifilaments,and cabled structures comprised of either or both monofilaments andmultifilaments. Such yarns can be provided for incorporation into wovenor nonwoven textile structures.

As used herein, the term “fibers” can include staple fibers (smalldiameter fibers of varying lengths typically formed from nylons orpolyamides which may be consolidated such as by needling into a cohesivemat typically used as a batt in press felts) and the like which areknown and used in the manufacture of industrial textiles.

As used herein, the term “film” refers to a thin, flexible sheetcomprised of one or more layers of a thermoplastic polymer which hasbeen uniaxially or biaxially oriented.

As used herein, the term “dry lubricant” refers to any material whichcan be provided in dry particulate form for incorporation with theselected thermoplastic polymer. For the purposes of the presentinvention, dry lubricants include molybdenum disulphide, tungstendisulphide, boron nitride, and soft metals including indium (In), lead(Pb), tin (Sn), bismuth (Bi), cadmium (Cd) and silver (Ag).

As used herein, the expression “% pbw” refers to the percentage parts byweight of the entire composition which is comprised of either the drylubricant or the thermoplastic polymer.

In relation to the particulate matter of the dry lubricants used in thethermoplastic polymers of the invention, their dimensions are expressedin relation to the average particle size, in microns (μ, wherein1μ=1×10⁻⁶ m); or nanometers (wherein 1 nanometer=1×10⁻⁹ m). In thethermoplastic polymeric elements of the invention, the dry lubricant istypically provided as a very small particle having an average particlesize from about 0.05μ to about 100μ.

Molybdenum disulphide is an inorganic compound with chemical formulaMoS₂. Its appearance and feel are similar to graphite and it is usedwidely as a solid lubricant because of its low frictional properties. Itis known to “fill” other polymers, in particular polyamides, with thismaterial. Several non-limiting examples of polymers to which molybdenumdisulphide has been added include Nylatron™ (trade mark of DSMPlastics), Teflon™ (trade mark of Du Pont for polytetrafluoroethylene)and Vespel™ (trade mark of Du Pont for a polyimide based polymer).Others are known and used.

Tungsten disulphide is also an inorganic chemical compound, having themolecular formula WS₂. It occurs naturally as the rare mineral calledtungstenite and has a layered structure similar to that of MoS₂; it isone of the most lubricious substances known. Tungsten disulphide wasoriginally developed by NASA as a dry lubricant for spacecraftcomponents operating in a vacuum. It is known to use this material inplastic mouldings, bearings, gearboxes, cutting and forming tools,threaded and splined components to reduce fretting, galling and seizing,and in various other applications where friction reduction is important

Boron nitride is also an inorganic chemical compound, with formula BN,consisting of equal numbers of boron (B) and nitrogen (N) atoms. BNexists in both a crystalline, diamond-like form as well as a hexagonalform similar to graphite; it is the hexagonal form which is commonlyused. Boron nitride is not found in nature and is produced from boricacid or boron trioxide.

Soft metals, such as indium (In), lead (Pb), tin (Sn), bismuth (Bi),indium (In), cadmium (Cd), silver (Ag), are naturally occurring elementsknown to possess lubrication properties due to their low shear strengthand plasticity.

The present invention concerns oriented, thermoplastic polymericelements for use in industrial textiles, and into which an effectiveamount of very small particulates, having an average particle size fromabout 0.05μ to about 100μ, and comprised of a dry lubricant, has beenblended prior to extrusion. The dry lubricant is preferably selectedfrom at least one of molybdenum disulphide, tungsten disulphide, boronnitride, or at least one soft metal such as indium (In), lead (Pb), tin(Sn), bismuth (Bi), cadmium (Cd) and silver (Ag). The present inventionalso concerns industrial textiles, particularly papermaking andfiltration fabrics, including these novel polymeric elements. The drylubricant may be incorporated into the polymer resin from which thepolymeric element is extruded by means of a masterbatch in quantitiessufficient to provide an amount of the dry lubricant between about 0.1%parts by weight (pbw) up to about 10% pbw, based on the total weight ofthe polymeric element. The masterbatch consists of a polymer, preferablya polyester, which is enhanced with from about 15% - 20% pbw of the drylubricant, such as one of more of the materials listed above. Themasterbatch is incorporated into the polymer from which the fibers, yarnor film are extruded in amounts sufficient to provide a finalconcentration in the extrudate that is from about 0.1% pbw up to about10% pbw. Alternatively, the dry lubricant can conveniently be added tothe extrudate using a gravity feed, or similar apparatus, located nearthe extruder throat. Concentrations of the dry lubricant below about0.1% do not appear to provide marked improvements in the abrasionresistance of the resultant fibers, yarn or film, while concentrationsin excess of about 10% may not provide further beneficial effects.Preferably, the concentration of the dry lubricant in the extruded andoriented fibers, yarn or film will be from about 0.5% to about 7% pbw.Most preferably, the concentration of the dry lubricant in the extrudedfibers, yarn or film is between 1%-5% pbw.

Where a polyester is used to construct the polymeric element, this canbe selected from such as are commonly used in the manufacture ofmonofilaments and the like and which are suitable for use in industrialtextiles such as papermaking fabrics. Preferably the polyester isselected from the group consisting of polyethylene terephthalate (PET),polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and thelike. Polyester alloys and polymer mixtures including a polyester, suchas a PET-TPU blend as described in U.S. Pat. No. 5,169,711 (Bhatt) andother similar polyesters such as are commonly used in the manufacture ofindustrial textiles for papermaking and like applications are suitable.

Preferably, the polyester into which the masterbatch is incorporatedwill have an Intrinsic Viscosity (IV) of at least 0.55; preferably theIV will be from about 0.60 to about 1.0. More preferably, the IV of thepolyester will be from about 0.80 to about 0.95 so as to provide a finalpolymeric element with physical properties suitable for use inpapermakers and similar industrial textiles. For these types of fabricapplications, the IV of the polyester of the finished polymeric elementshould be at least 0.7 or higher. Intrinsic Viscosity, where identifiedherein, is measured on a solution of the polyester in a mixed solventcomprising a 60:40 pbw mixture of phenol and (1,1,2,2)-tetrachloroethaneat 30° C. The IV can also be measured using a 50:50 pbw mixture oftrifluoroacetic acid and dichloromethane.

In general, the masterbatch polyester into which the dry lubricant isincorporated will have an IV that is lower than the IV of the polyesterinto which it is added. However, the IV of the masterbatch polyester canbe equal to or greater than that of the polyester into which it isadded. Extrusion requires addition of heat which will normally lower theintrinsic viscosity of the polyester and degrade the final properties ofthe resultant polymeric element.

The dry lubricant used in the present invention should be of asubstantially uniform particulate size and configuration. Preferably,the dry lubricant has an average particle size of from about 0.05 toabout 100μ. Preferably, the dry lubricant is uniformly dispersed withinthe chosen polymer and in the final polymeric element.

The blending of the chemical constituents from which the yarns, fibersand films of the present invention are extruded can be carried out inany sequence suitable to the manufacturing operation. However, it hasbeen found convenient to dry blend the polymer material with therequired quantity of the masterbatch material to obtain the desiredconcentration of dry lubricant in the final product and to ensure areasonably uniform dispersion of the dry lubricant. Alternatively thedry lubricant can conveniently be added by a metered gravity feed in aknown manner at the extruder.

For monofilaments, after blending the chemical constituents, the yarnsare prepared according to customary techniques. The molten polymer,together with the dry lubricant with which it is blended, as well as anyother additives (such as processing aids, colorants, and the like), isextruded through a die into a quench medium, after which it is oriented.The monofilaments can be extruded according to known methods usingeither a single screw or a twin screw extruder; it is anticipated thattwin screw extrusion will provide more uniform blending of the drylubricant with the chosen polymer and hence is presently preferred. Ingeneral, the diameter of circular cross-section monofilaments formedfrom the polymer blend of the present invention will be from about 0.08mm to about 1.2 mm, and is preferably from about 0.12 mm to about 0.5mm. After extrusion, the extruded polymeric material will undergo anorientation step, involving a uniaxial or biaxial stretching andrelaxation, as appropriate and as known in the art of polymer extrusion,so as to align the polymer chains of the extrudate, and thus enhance thephysical properties of the resulting material.

As noted above, the present invention is applicable to any type ofindustrial textile intended for conveying or filtration and which can beconstructed from polymeric elements, including, but not limited to,textiles constructed by weaving, helical or spiral coil assembly,pre-crimped yarn assembly, and selectively slit and embossed film, ineach case to provide a single layer textile, or one or more outer layersin a multi-layer construction. In addition, where it is sought tominimize discontinuity at the seaming areas of such textiles by usingseaming elements which are constructed of polymers either identical to,or closely compatible with, polymers from which the textile body isconstructed, the use of the polymeric elements of the present inventionfor such seaming elements can be particularly advantageous in providingimproved physical properties, either for industrial textiles of thepresent invention, or for industrial textiles not of the invention butconstructed of polymers with which the polymers of the seaming elementscan be selected to be compatible. Such seaming elements would include,but not be limited to, spiral seaming coils, and various constructionsdesigned to engage the respective textile edges and be connectedtogether, in particular seaming lumens such as disclosed in WO2010/121360 (Manninen), and elements formed from films such as disclosedin PCT/CA2010/001955 (Manninen et al.).

The invention therefore seeks to provide an extruded and orientedthermoplastic polymeric element for use in an industrial textile,wherein the polymeric element is constructed of a material selected fromyarn material, fiber material and film, and comprises

(i) a thermoplastic polymer; and

(ii) at least one dry lubricant, selected from the group consisting ofmolybdenum disulphide (MoS₂), tungsten disulphide (WS₂), boron nitride(BN), and a soft metal, wherein the dry lubricant comprises particulatematter having an average particle size in a range of between about 0.05μand about 100μ (5.0×10⁻⁸ m and about 1.0×10⁻⁴ m), and is present in thepolymeric element in an amount from between about 0.1% and about 10%parts by weight (pbw), based on a total weight of the polymeric element.

The invention further seeks to provide an industrial textile comprisingat least one extruded and oriented thermoplastic polymeric element,wherein each of the at least one polymeric element is constructed of amaterial selected from yarn material, fiber material and film, andcomprises

(i) a thermoplastic polymer; and

(ii) at least one dry lubricant, selected from the group consisting ofmolybdenum disulphide (MoS₂), tungsten disulphide (WS₂), boron nitride(BN) and a soft metal, wherein the dry lubricant comprises particulatematter having an average particle size in a range of between about 0.05μand about 100μ (5.0×10⁻⁸ m and about 1.0×10⁻⁴ m) and is present in thepolymeric element in an amount from between about 0.1% and about 10%parts by weight (pbw), based on the total weight of the polymericelement.

The invention further seeks to provide an industrial textile comprisingheatset machine direction (MD) and cross-machine direction (CD)elements, wherein at least 25% of the CD elements are extruded andoriented thermoplastic polymeric elements, each polymeric elementcomprising

(i) a thermoplastic polymer; and

(ii) at least one dry lubricant, selected from the group consisting ofmolybdenum disulphide (MoS₂), tungsten disulphide (WS₂), boron nitride(BN) and a soft metal, wherein the dry lubricant comprises particulatematter having an average particle size in the range of between about0.05μ and about 100μ (5.0×10⁻⁸ m and about 1.0×10⁻⁴ m), and is presentin the polymeric element in an amount from between about 0.1% and about10% parts by weight (pbw), based on the total weight of the polymericelement.

The invention further seeks to provide an industrial textile comprisingheatset machine direction (MD) and cross-machine direction (CD)elements, wherein at least 25% of the MD elements are extruded andoriented thermoplastic polymeric elements, each polymeric elementcomprising

(i) a thermoplastic polymer; and

(ii) at least one dry lubricant, selected from the group consisting ofmolybdenum disulphide (MoS₂), tungsten disulphide (WS₂), boron nitride(BN) and a soft metal, wherein the dry lubricant comprises particulatematter having an average particle size in the range of between about0.05μ and about 100μ (5.0×10⁻⁸ m and about 1.0×10⁻⁴ m), and is presentin the polymeric element in an amount from between about 0.1% and about10% parts by weight (pbw), based on the total weight of the polymericelement.

In the polymeric elements and the industrial textiles of the invention,preferably the thermoplastic polymer is selected from the groupconsisting of polyethylene terephthalate (PET), polybutyleneterephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylenenaphthalate (PEN), blends of PET and a thermoplastic polyurethane,polyether ether ketone (PEEK), polyphenylene sulphide (PPS), 1,4cyclohexanedimethanol-terephthalate-co-isophthalate (PCTA).

Alternatively, the at least one dry lubricant is selected from the groupconsisting of tungsten disulphide (WS₂), boron nitride (BN), and a softmetal, and the thermoplastic polymer comprises at least one polyamide.Preferably such polyamide is selected from at least one of thefollowing:

PA-6: polycaprolactam or nylon-6 or polyamide-6

PA-6/6: polyhexamethylene adipamide or nylon 6/6 or polyamide-6/6

PA-6/10: poly(hexamethylene sebacamide or nylon-6/10 or polyamide-6/10

PA-11: poly(11-aminoundecanoic acid) or nylon-11 or polyamide-11

PA-6/12: poly(hexamethylene dodecanoamide) or nylon-6/12 orpolyamide-6/12

PA-10: also known as nylon-10 or polyamide-10

PA-12: also known as nylon-12 or polyamide-12 polyphthalamide (PPA).

Preferably, the soft metal is selected from indium (In), lead (Pb), tin(Sn), bismuth (Bi), cadmium (Cd), and silver (Ag).

Preferably, the dry lubricant comprises between about 0.5% and about 7%pbw of the total weight of the polymeric element, and more preferablybetween about 1% and about 5% pbw of the total weight of the polymericelement.

Preferably, the average particle size of the particulate matter of thedry lubricant is in a range of between about 0.1μ and 50μ (1.0×10⁻⁷ mand about 5.0×10⁻⁵ m) ; more preferably between about 0.5μ and about 20μ(5.0×10⁻⁷ m and about 2.0×10⁻⁵ m).

The polymeric element can be of any suitable form depending on theintended end use, including a film comprising at least one layer; afiber material, which can comprise a staple fiber material; and a yarnmaterial having a construction selected from monofilament yarn,multifilament yarn, spun yarn, cabled yarn and sheathed yarn.

In one embodiment, the polymeric elements of the invention can beconstructed from a yarn material or a film for use as seaming elements,which can be used for seaming industrial textiles or many types, inparticular industrial textiles of the present invention.

The industrial textiles of the invention can comprise woven structuresincluding warp yarns and weft yarns, or nonwoven structures including MDand CD yarns. Alternatively, they can comprise one or more layers offilm; or nonwoven structures wherein the at least one polymeric elementcomprises a plurality of interconnected helically coiled yarns.Additionally, the industrial textiles of the invention can comprise aseaming element constructed as a polymeric element according to theinvention.

The industrial textiles of the invention can be constructed and arrangedto be used as industrial filtration fabrics or conveying fabrics, and inparticular to be used in a section of a papermaking machine selectedfrom a forming section, a press section and a dryer section. For use ina papermaking machine, the fabrics can be forming fabrics, pressfabrics, dryer fabrics, particularly through air dryer fabrics.

Where the polymeric element is a polyester, preferably the polyester hasan intrinsic viscosity of at least 0.7, determined using a mixtureselected from a 60:40 pbw mixture of phenol and(1,1,2,2)-tetrachloroethane and a 50:50 pbw mixture of trifluoroaceticacid and dichloromethane.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the drawings, inwhich

FIG. 1 is a graph showing the results of dry friction testing of amonofilament made in accordance with the teaching of the presentinvention in comparison with three other monofilaments according to theprior art;

FIG. 2 is a graph showing percent retained tensile loss under dry testconditions of a monofilament prepared in accordance with the teachingsof the present invention in comparison to two other monofilamentsaccording to the prior art;

FIG. 3 is a graph showing the results of dry friction testing ofmonofilaments prepared in accordance with the teachings of the inventionin comparison to one other monofilament according to the prior art; and

FIG. 4 is a graph providing comparative data for wet friction testing ofthree monofilaments prepared in accordance with the teachings of theinvention in comparison to two other monofilaments.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring first to FIG. 1, this is a graph demonstrating the amount offorce required to move a monofilament which is in contact with a solidfriction pin a measured distance according to the capstan friction testmethod described in ASTM D 3108-95, entitled “Standard Test Method ofCoefficient of Friction, Yarn to Solid Material”. The X-axis indicatesthe distance as measured in inches, and the Y-axis indicates the forceas measured in pounds (lb.).

In FIG. 1, the results of testing four monofilaments, identified as A,B, C and D, according to the test method are presented. Monofilament Awas a 0.40 mm diameter, circular cross-section, melt extruded andoriented monofilament comprised of PET which further included 5% pbw(parts by weight) of a dry lubricant, molybdenum disulphide, in particleform uniformly distributed throughout the monofilament. The molybdenumdisulphide particles had an average particle size of about 6μ, and weresupplied by the manufacturer, Polyvel, Inc. of 100 Ninth Street,Hammonton, N.J. 08037. Monofilament A was prepared in accordance withthe invention and had an Intrinsic Viscosity (IV) of about 0.75.

Comparison monofilaments B, C and D were also prepared in a mannersimilar to that of monofilament A but did not contain any dry lubricantdispersed in the polymer melt. Monofilament B did not contain a drylubricant, but was otherwise substantially similar to monofilament A, inthat it was a 0.40mm diameter circular cross-section monofilament, wascomprised of the same polyester (PET), and was produced to have anIntrinsic Viscosity (IV) of about 0.75. Monofilament C contained a knownlubricant which was not a dry lubricant, but was otherwise alsosubstantially similar to monofilament A. Monofilament D wassubstantially similar to monofilament B, but was produced so as to havea lower IV, of less than 0.7. Following their preparation, themonofilaments A, B, C and D were then tested so as to determine andcompare the force required to move them in a standard test similar tothat described in ASTM D 3108-95, the test being modified from thatdescribed in ASTM D 3108-95 only in order to provide a constant anduniform tension to the monofilaments.

In the modified version of the ASTM D 3108-95 test used to obtain theresults shown in FIG. 1, the adjustable input tension applied to themonofilaments prior to the friction pin was replaced with a 50 g masswhich was found to be appropriate for the size of the strands. In thetest, the 50 g mass was first suspended from one end of a yarn; the yarnwas then wrapped at a wrap angle of 450° about a capstan friction pin.The opposite end of the yarn was then attached to a constant rate ofextension (CRE) type tensile testing machine provided with anappropriate force gauge. The monofilament was then pulled a knowndistance and the amount of force required to move that distance wasmeasured (in pounds). Each monofilament was exposed to the identicaltest conditions (applied mass, wrap angle, friction pin) and the testswere repeated under the same conditions a number of times, using thesame materials, so as to obtain a statistically significant result.

The results graphed in FIG. 1 show that the average force required topull the inventive monofilament A through the apparatus was, on average,about 0.30 lb, whereas the force required to pull the prior artmonofilaments B, C and D through the same apparatus, under the identicaltest conditions, was much higher and ranged from about 1.7 lb formonofilaments B and C, to about 1.3 lb for monofilament D which had thelowest IV of the monofilaments tested. The data presented in FIG. 1 thusshow that monofilaments prepared in accordance with the teachings of thepresent invention require much less force to pull through a knowndistance at a standard wrap angle around a common capstan friction pin,and thus have a much lower coefficient of friction, than comparablemonofilaments which do not contain a proportion of the dry lubricant.

The coefficient of friction (μ) can be determined using the formula:

$\mu = \frac{\ln\left\lbrack \frac{T_{afterwrap}}{T_{beforewrap}} \right\rbrack}{{wrap}\mspace{14mu} {angle}}$

In the above formula, T_(after wrap) is the average force required topull the monofilament (i.e. the Y-axis values in FIG. 1), andT_(before wrap) is the 50 g mass which was suspended from themonofilament before it wrapped the friction capstan at a wrap angle of450°, which corresponds to 7.854 radians.

Referring next to FIG. 2, this is a graph showing the percentage tensileloss under dry test conditions of monofilaments (A) prepared inaccordance with the teachings of the present invention, in comparison totwo similar monofilaments (E and F) of the prior art, which did notinclude a dry lubricant.

In this test, the tensile strength of the various monofilament samplesis first determined using a suitable apparatus and test method. Forexample, a CRE test apparatus, such as an Instron Tensile Testingmachine available from Instron Worldwide of Norwood, Mass. would beappropriate; other tensile testing apparatus may also be satisfactory. Astandard procedure, such as that described in ASTM D2256 “Standard TestMethod for Tensile Properties of Yarns by the Single-Strand Method” maybe used. Any suitable test method can be selected, provided that eachsample is tested using the same procedure and test apparatus as allother samples, so that the results obtained are directly comparable andprovide a reliable determination of the maximum tensile strength of thestrand.

Following determination of the yarn tensile strength prior to testing, aknown length of each monofilament sample was fixedly attached to oneside of a so-called “squirrel cage” abrasion test apparatus. In thetest, the sample was draped over a rotatable, grooved ceramic wheel; theopposite end of the sample was attached to a known mass so that thesample rested in positive contact with the ceramic wheel. The ceramicwheel was then rotated at constant speed under power with themonofilament samples resting in contact with the wheel and the sameapplied load attached to each, and the number of rotations (cycles)recorded. The monofilament samples were removed from the test apparatusat regular intervals of 100,000 cycles, and the tensile strength of eachsample was remeasured using the same test apparatus and method employedto determine its original maximum tensile strength. The tensile strengthof each sample at each interval was compared to its original tensilestrength prior to abrasion under test, and the results were plotted as afunction of their loss in tensile strength (Tensile Loss (%)) incomparison to the number of cycles to which the samples were exposed.

In the data presented graphically in FIG. 2, monofilament A was a 0.35mm diameter, circular cross-section, melt extruded and orientedmonofilament of the invention, comprised of PET and including 1.7% pbwof a dry lubricant, tungsten disulphide, in particle form uniformlydistributed throughout the monofilament. The tungsten disulphide waspurchased as dry particles from M.K. IMPEX Canada, 6382 Lisgar Drive,Mississauga, Ontario L5N 6X1, Canada and the particle size as providedby the supplier ranged from about 0.1 to 6.0 microns. To prepare themonofilament A, the tungsten disulphide was uniformly dry blended withthe PET granules prior to monofilament extrusion; monofilament sampleswere then extruded according to standard industry practices.

Monofilament E was a 0.35 mm diameter monofilament comprised of a blendof about 60% PET and 40% thermoplastic polyurethane prepared in themanner described in U.S. Pat. No. 5,502,120 (Bhatt et al.) and which didnot contain any dry lubricant. Monofilament F was a 0.35 mm diameterpolyamide monofilament such as would be used in the manufacture ofindustrial textiles and which was prepared in accordance with theteachings of U.S. Pat. No. 6,828,681. Monofilament F was comprised of ablend of approximately 95% pbw polyamide 6/10 & 5% pbw polyamide 11 anddid not contain any dry lubricant.

As shown in the graph of FIG. 2, monofilament A, comprised of PET and1.7% pbw tungsten disulphide particles, lost less than 10% of itsoriginal tensile strength following exposure to 600,000 rotation cycleson the test apparatus. In comparison, monofilament E, comprised of theblend of PET and thermoplastic polyurethane, lost about 30% of itsoriginal tensile strength whilst the polyamide sample, monofilament F,lost about 87% of its original tensile strength following exposure to600,000 cycles.

The test data displayed graphically in FIG. 2 thus show that polymericmonofilaments including about 1.7% pbw of a dry lubricant are moreresistant to abrasion, as determined by the percent tensile strengthremaining in them following exposure to prolonged dry abrasive effects,than are comparable monofilaments that do not contain a dry lubricant,in this case tungsten disulphide.

Referring now to FIG. 3, this is a graph showing the results of frictiontesting of a monofilament sample (A) that was prepared in accordancewith the teachings of the invention, in comparison to a secondmonofilament sample (B) which did not contain a dry lubricant. The testwas performed according to the methods described in relation to FIG. 1.In this case, monofilament A was a 0.35 mm diameter circularcross-section monofilament comprised of PET into which 1.7% pbw oftungsten disulphide particles having a particle size ranging between 0.1and 6 microns had been uniformly dry blended prior to extrusion.Monofilament B did not contain any dry lubricant, but was otherwisesubstantially identical to monofilament A, being also a 0.35 mm diametercircular cross-section PET monofilament. The intrinsic viscosity of thepolyester of both monofilaments A and B was the same.

Both monofilaments were tested in accordance with the modified versionof test method ASTM D 3108-95 entitled “Standard Test Method ofCoefficient of Friction, Yarn to Solid Material” as described above.Both monofilaments were tensioned at a wrap angle of 450° around thefriction capstan using the same 50 g weight and were pulled a distanceof about 9 inches; the force required to pull the monofilaments aroundthe friction capstan was measured using a CRE type tensile testingmachine provided with a suitable force gauge. Measurements of the forcerequired to pull the monofilaments around the capstan were takencontinuously as shown in the graph.

The data presented in FIG. 3 show that polyester monofilaments includinga dry lubricant according to the invention, specifically 1.7% pbwtungsten disulphide particles whose sizes range between about 0.1 and 6microns, require significantly less force to move through the measureddistance than comparable monofilaments that do not contain the drylubricant.

Referring now to FIG. 4, this is a graph demonstrating the amount offorce required to move a monofilament which is in contact with a solidfriction pin a measured distance according to the capstan friction testmethod described in ASTM D 3108-95 entitled “Standard Test Method ofCoefficient of Friction, Yarn to Solid Material”. The test was modifiedin this instance from that described in ASTM D 3108-95 in that the yarnsand capstan friction pin were immersed in a water bath. The intent ofthis test was to determine the force required to pull the monofilamentsthe required distance when exposed to water and to further determinewhether any of the monofilaments behaved differently in such conditionsfrom the others.

In FIG. 4, the results of testing five monofilaments, identified as G,H, I, J and K, in accordance with the modified wet friction test methodare presented. Other than with respect to the addition of a drylubricant into the polymer melt, all five monofilaments weresubstantially similar, each being melt extruded from pelletized PPS(polyphenylene sulphide) resin in a manner similar to that describedabove in relation to the extrusion of PET; all the monofilaments wereextruded so as to provide a rectangular cross-section measuring 0.60 mmin width by 0.30 mm in height. The composition of each monofilament withrespect to the dry lubricant additive was as follows:

Monofilament G: 2.0% pbw tungsten disulphide

Monofilament H: 1.1% pbw tungsten disulphide

Monofilament I: 1.0% pbw molybdenum disulphide

Monofilament J: 0.0% pbw dry lubricant

Monofilament K: 0.0% pbw dry lubricant +1% pbw colorant

In the monofilament samples of FIG. 4, samples G and H contained 2% and1.1% pbw respectively of tungsten disulphide. This material was obtainedas dry particles from M.K. IMPEX Canada, 6382 Lisgar Drive, Mississauga,Ontario L5N 6X1, Canada and had a particle size as provided by thesupplier of between about 0.1 and 6.0 microns. The tungsten disulphidewas added in dry powder form to, and was compounded with, the pelletizedPPS. The PPS with which the dry lubricants were blended was Fortron PPSwhich is a high-temperature linear PPS and was purchased from TiconaEngineering Polymers, a business unit of Celanese Corporation of Dallas,TX. The uniformly blended polymer resin pellets together with the drylubricant were then melt extruded and drawn as rectangular crosssectional monofilaments.

Sample I was prepared in an identical manner to samples G and H with theexception that 1% pbw of molybdenum disulphide dry lubricant was used inplace of the tungsten disulphide. The molybdenum disulphide had anaverage particle size of about 6 microns. The molybdenum disulphide wassupplied by the manufacturer, Polyvel, Inc. of 100 Ninth Street,Hammonton, N.J. 08037.

Monofilament J was produced identically to monofilaments G, H and I butdid not contain any dry lubricant additive; and monofilament K was alsoproduced similarly, without a dry lubricant, but 1% pbw of acommercially available colorant was added to the polymer melt.

In the modified version of the ASTM D 3108-95 test used to obtain theresults shown in FIG. 4, the apparatus was modified to include a waterbath in which the capstan friction pin, and hence the yarns, wereimmersed. The arrangement was otherwise essentially identical to thatdescribed in relation to the test method used to obtain the data inFIG. 1. Each yarn was attached at one end to a 50g mass, and wasattached at the other to a CRE type tensile testing machine providedwith an appropriate force gauge. Each yarn was then wrapped at a wrapangle of 450° about the capstan friction pin, which was under water. Themonofilament was then pulled a known distance and the amount of forcerequired to move that distance was measured, in pounds. Eachmonofilament was exposed to the identical test conditions (applied mass,wrap angle, friction pin) and the tests were repeated under the sameconditions a number of times, using the same materials, so as to obtaina statistically reliable and significant result.

The results graphed in FIG. 4 show that the average force required topull the inventive monofilaments G, H and I through the apparatus was,on average, about 0.40 lb while the force required to pull the prior artmonofilament J, and the monofilament K which contained the colorant wasat least twice as great, at about 0.80 lb. The data presented in

FIG. 4 thus shows that monofilaments comprised of a blend of PPS and drylubricant, and prepared in accordance with the teachings of the presentinvention, require much less force to pull through a known distance at astandard wrap angle around a common capstan friction pin while immersedin water, and thus have a much lower coefficient of friction, thancomparable monofilaments which do not contain a dry lubricant.

The experimental information presented in FIGS. 1 to 4 thus shows thatmonofilaments prepared in accordance with the teachings of the presentinvention possess a lower coefficient of friction (as expressed in termsof the amount of force required to move them a known distance accordingto standard test methods), and exhibit a greater resistance to abrasion(as measured by percent tensile loss following exposure to dry abrasionconditions) in comparison to comparable monofilaments which do notcontain a dry lubricant such as molybdenum disulphide or tungstendisulphide in amounts ranging from about 1.1% to 5% pbw. Alternatively,as noted above, it is expected that many other dry lubricants willprovide similar results in monofilaments and films prepared inaccordance with the teachings of the present invention, for exampleboron nitride, or a soft metal such as one or more of indium, lead, tin,bismuth, cadmium or silver.

The yarns of the invention, constructed as monofilaments, multifilamentsor otherwise, can be woven or arranged into industrial textiles,particularly papermaking fabrics, according to known and conventionaltechniques. The fabrics may be woven using conventional equipment, orthey may be assembled from multiple yarn arrays according to methodsdescribed elsewhere (see e.g., U.S. Pat. No. 6491794 (Davenport) and WO05/056920 (Eagles)).The chosen weave construction or yarn arrangementwill depend on the intended end use application for which the fabric isdestined.

Where the polymeric elements of the present invention are provided asyarns, such as monofilaments, they may be found particularlysatisfactory and effective when used in combination with other polymericyarn materials which do not contain dry lubricants. For example, theyarn materials of the invention may be used in woven constructions wherethey form the CD elements located on the MS of the fabric. In such acase, they may comprise from as few as 25% to as much as 100% of the MSCD yarns. The yarn materials of the invention may also be used as atleast a portion of the MD elements of the textiles, or as much as 100%of the MD elements on the wear side of the textiles. As a furtheralternative, the entire fabric may be assembled from monofilamentsaccording to the present invention.

After weaving or other fabric assembly processes, textiles constructedof yarn materials are heatset according to conventional techniques tostabilize the fabric structure. Heatsetting conditions will vary withthe chosen polymers, yarn materials, their size and the weaveconstruction, but will typically involve heating the fabric undertension while it is mounted on a heatsetting frame such as is normallyused for this purpose.

Where the polymeric element is provided as a film, this can be as ahomolayer or one or more outer layers in a multilayer textile, as notedabove. In particular, the industrial textiles of the invention canadvantageously be provided as one or more layers of slit and profiledfilms such as are described in PCT/CA2010/001956 (Manninen).

Further, as noted above, the polymeric elements of the present inventioncan be used for various types of seaming elements for industrialtextiles, by incorporating the dry lubricant into the polymer from whichthe seaming element, such as a spiral coil, seaming lumen or film isconstructed.

As discussed above, the dry lubricants act to improve the abrasionresistance of the polymeric element while simultaneously lowering thecoefficient of friction of the resultant yarns and textiles madetherefrom. In addition to these benefits, the present invention alsoprovides the ability to take advantage of the physical properties ofpolyester based materials over polyamide monofilaments of the prior art,including moisture stability and dimensional stability, in thatpolyester yarns do not expand or contract following wet-to-dry cyclingin water and air. The physical and chemical properties of the polymericelements of the present invention, other than the increased abrasionresistance and reduced coefficient of friction as discussed herein, aresubstantially similar to those already incorporated into knownindustrial textiles, thus reducing or eliminating any issues of any needto modify fabric design to accommodate the use of the polymeric elementsof the invention. In particular, it is now possible to manufacturefabrics entirely from polyester based materials while reducing theoverall coefficient of friction of the fabric and improving itsresistance to wear in comparison to prior art fabrics which include aportion of polyamide based materials.

1. An extruded and oriented thermoplastic polymeric element for use inan industrial textile, wherein the polymeric element is constructed of amaterial selected from yarn material, fiber material and film, andcomprises (i) a thermoplastic polymer; and (ii) at least one drylubricant, selected from the group consisting of molybdenum disulphide(MoS₂), tungsten disulphide (WS₂), boron nitride (BN), and a soft metal,wherein the dry lubricant comprises particulate matter having an averageparticle size in a range of between about 0.05μ and about 100μ (5.0×10⁻⁸m and about 1.0×10⁻⁴ m), and is present in the polymeric element in anamount from between about 0.1% and about 10% parts by weight (pbw),based on a total weight of the polymeric element.
 2. A polymeric elementaccording to claim 1, wherein the thermoplastic polymer is selected fromthe group consisting of polyethylene terephthalate (PET), polybutyleneterephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylenenaphthalate (PEN), blends of PET and a thermoplastic polyurethane,polyether ether ketone (PEEK), polyphenylene sulphide (PPS), 1,4cyclohexanedimethanol-terephthalate-co-isophthalate (PCTA).
 3. Apolymeric element according to claim 1, wherein the at least one drylubricant is selected from the group consisting of tungsten disulphide(WS₂), boron nitride (BN), and a soft metal, and the thermoplasticpolymer comprises at least one polyamide.
 4. A polymeric elementaccording to claim 3, wherein the at least one polyamide is selectedfrom at least one of PA-6, PA-6/6, PA-6/10, PA-6/12, PA-11, PA-10, PA-12and polyphthalamide (PPA).
 5. A polymeric element according to claim 1,wherein the soft metal is selected from indium (In), lead (Pb), tin(Sn), bismuth (Bi), cadmium (Cd), and silver (Ag).
 6. A polymericelement according to claim 1, wherein the dry lubricant comprisesbetween about 0.5% and about 7% pbw of the total weight of the polymericelement.
 7. A polymeric element according to claim 6, wherein the drylubricant comprises between about 1% and about 5% pbw of the totalweight of the polymeric element.
 8. A polymeric element according toclaim 1, wherein the average particle size of the particulate matter ofthe dry lubricant is in a range of between about 0.1μ and 50μ (1.0×10⁻⁷m and about 5.0×10⁻⁵ m).
 9. A polymeric element according to claim 8,wherein the average particle size of the particulate matter of the drylubricant is in a range of between about 0.5μ and about 20μ (5.0×10⁻⁷ mand about 2.0×10⁻⁵ m).
 10. A polymeric element according to claim 1,wherein the polymeric element comprises a film comprising at least onelayer.
 11. (canceled)
 12. (canceled)
 13. A polymeric element accordingto claim 1, wherein the polymeric element comprises a yarn materialhaving a construction selected from monofilament yarn, multifilamentyarn, spun yarn, staple fiber material, cabled yarn and sheathed yarn.14. A polymeric element according to claim 1, wherein the polymericelement comprises a material selected from a yarn material and film, andis a seaming element.
 15. An industrial textile comprising at least oneextruded and oriented thermoplastic polymeric element, wherein each ofthe at least one polymeric element is constructed according to claim 1.16.-27. (canceled)
 28. An industrial textile according to claim 15,wherein the textile comprises a woven structure including warp yarns andweft yarns.
 29. An industrial textile according to claim 15, wherein thetextile comprises a nonwoven structure including MD and CD yarns.
 30. Anindustrial textile according to claim 15, wherein the textile comprisesa nonwoven structure and the at least one polymeric element comprises aplurality of interconnected helically coiled yarns.
 31. An industrialtextile according to claim 15, further comprising a seaming element. 32.An industrial textile comprising machine direction (MD) andcross-machine direction (CD) elements, wherein at least 25% of theelements of a set selected from the MD elements and the CD elements areextruded and oriented thermoplastic polymeric elements, each polymericelement comprising: (i) a thermoplastic polymer; and (ii) at least onedry lubricant, selected from the group consisting of molybdenumdisulphide (MoS₂), tungsten disulphide (WS₂), boron nitride (BN) and asoft metal, wherein the dry lubricant comprises particulate matterhaving an average particle size in the range of between about 0.05μ andabout 100μ (5.0×10⁻⁸ m and about 1.0×10⁻⁴ m), and is present in thepolymeric element in an amount from between about 0.1% and about 10%parts by weight (pbw), based on the total weight of the polymericelement.
 33. (canceled)
 34. An industrial textile according to claim 32,wherein the soft metal is selected from indium (In), lead (Pb), tin(Sn), bismuth (Bi), cadmium (Cd), and silver (Ag).
 35. An industrialtextile according to claim 15, constructed and arranged to be used as atleast one of an industrial filtration fabric and a conveying fabric. 36.(canceled)
 37. An industrial textile according to claim 15, constructedand arranged to be used in a section of a papermaking machine selectedfrom a forming section, a press section and a dryer section, and thefabric is selected from a forming fabric, a press fabric, a dryer fabricand a through air dryer fabric. 38.-41. (canceled)
 42. A polymericelement according to claim 1, wherein the thermoplastic polymer is apolyester having an intrinsic viscosity of at least 0.7, determinedusing a mixture selected from a 60:40 pbw mixture of phenol and(1,1,2,2)-tetrachloroethane and a 50:50 pbw mixture of trifluoroaceticacid and dichloromethane.
 43. An industrial textile according to claim15, wherein the thermoplastic polymer is a polyester having an intrinsicviscosity of at least 0.7, determined using a mixture selected from a60:40 pbw mixture of phenol and (1,1,2,2)-tetrachloroethane and a 50:50pbw mixture of trifluoroacetic acid and dichloromethane.
 44. Anindustrial textile according to claim 32, constructed and arranged to beused as at least one of an industrial filtration fabric and a conveyingfabric.
 45. An industrial textile according to claim 32, constructed andarranged to be used in a section of a papermaking machine selected froma forming section, a press section and a dryer section, and the fabricis selected from a forming fabric, a press fabric, a dryer fabric and athrough air dryer fabric.
 46. An industrial textile according to claim32, wherein the thermoplastic polymer is a polyester having an intrinsicviscosity of at least 0.7, determined using a mixture selected from a60:40 pbw mixture of phenol and (1,1,2,2)-tetrachloroethane and a 50:50pbw mixture of trifluoroacetic acid and dichloromethane